Compilare: main.cpp: In function 'int main()': main.cpp:55:29: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int ja = 0, j = 0; j < divList[arr[i]].size(); ++j) { ~~^~~~~~~~~~~~~~~~~~~~~~~~ main.cpp:56:14: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while (ja < divList[arr[i - 1]].size() and divList[arr[i - 1]][ja] < divList[arr[i]][j]) ~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~ main.cpp:58:11: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (ja < divList[arr[i - 1]].size() and divList[arr[i - 1]][ja] == divList[arr[i]][j]) ~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~ main.cpp:65:29: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int ja = 0, j = 0; j < divList[arr[i]].size(); ++j) { ~~^~~~~~~~~~~~~~~~~~~~~~~~ main.cpp:66:14: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while (ja < divList[arr[i + 1]].size() and divList[arr[i + 1]][ja] < divList[arr[i]][j]) ~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~ main.cpp:68:11: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (ja < divList[arr[i + 1]].size() and divList[arr[i + 1]][ja] == divList[arr[i]][j]) ~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~ main.cpp:79:29: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int j = 0, ja = 0; j < divList[arr[x]].size() and !ok; ++j) { ~~^~~~~~~~~~~~~~~~~~~~~~~~ main.cpp:80:14: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while (ja < divList[arr[y]].size() and divList[arr[y]][ja] < divList[arr[x]][j]) ~~~^~~~~~~~~~~~~~~~~~~~~~~~ main.cpp:82:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (nextPos[x][j] >= y or (ja < divList[arr[y]].size() and divList[arr[y]][ja] == divList[arr[x]][j] and nextPos[x][j] == prevPos[y][ja])) ~~~^~~~~~~~~~~~~~~~~~~~~~~~ main.cpp:86:29: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int j = 0, ja = 0; j < divList[arr[y]].size() and !ok; ++j) { ~~^~~~~~~~~~~~~~~~~~~~~~~~ main.cpp:87:14: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while (ja < divList[arr[x]].size() and divList[arr[x]][ja] < divList[arr[y]][j]) ~~~^~~~~~~~~~~~~~~~~~~~~~~~ main.cpp:89:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (prevPos[y][j] <= x or (ja < divList[arr[x]].size() and divList[arr[x]][ja] == divList[arr[y]][j] and prevPos[y][j] == nextPos[x][ja])) ~~~^~~~~~~~~~~~~~~~~~~~~~~~ main.cpp: In member function 'void InputReader::advance()': main.cpp:13:32: warning: ignoring return value of 'size_t fread(void*, size_t, size_t, FILE*)', declared with attribute warn_unused_result [-Wunused-result] fread(buff, SIZE, 1, inFile); ^ main.cpp: In constructor 'InputReader::InputReader(const char*)': main.cpp:23:31: warning: ignoring return value of 'size_t fread(void*, size_t, size_t, FILE*)', declared with attribute warn_unused_result [-Wunused-result] fread(buff, SIZE, 1, inFile); ^